缝纫泡沫芯夹层结构低速冲击损伤分析

Exploring Damage Characteristics of Stitched Foam-Core Sandwich Structure under Low-Velocity Impact

在缝纫复合材料泡沫芯夹层结构低速冲击试验研究基础上,文章开展了低速冲击损伤数值分析。首先利用有限元软件分别对未缝纫和缝纫的复合材料泡沫芯夹层结构低速冲击下的损伤面积进行了数值估算,发现两者的上面板损伤面积均大于下面板的损伤面积,但两者的主要损伤模式不同,未缝纫夹层结构的主要损伤模式为上面板损伤,而缝纫夹层结构主要以泡沫芯材压碎损伤破坏为主。有限元计算结果与试验结果吻合较好,证明文中所建立模型的正确性。随后模拟计算了冲击能量、上面板厚度、泡沫芯材厚度、缝纫密度、落锤冲击位置等五个因素变化对缝纫泡沫芯复合材料夹层结构损伤面积的影响,并进行了相关的理论分析。

Sections 1 and 2 of the full paper explain our method of exploring damage characteristics.Their core is： ＂we use commercial finite element software to calculate respectively the damage areas of unstitched and stitched foam-core sandwich structures.The numerical simulation results show that the damage areas of upper panel are greater than those of the lower one for both the unstitched and stitched ones.But the main pattern of damage of the stitched foam-core sandwich structure is different from that of the unstitched foam-core sandwich structure.The upper panel damage is the main damage pattern for the unstitched foam-core sandwich structure,whereas crushing damage is that for the stitched foam-core sandwich structure.The finite element results have accorded well with experimental results,which prove the correctness of our finite element model.＂ Section 3 calculates the effects on damage areas of the following five factors： impact energy,thickness of upper panel,thickness of foam-core,stitched density,and the location of drop-hammer;it also presents some related theoretical analysis.Section 4 presents six preliminary conclusions.